The March Madness basketball tournament stirs emotions in even the most casual of sports fans. Watching young student-athletes compete for the thrill of victory or the agony of defeat without any financial gain is as pure as sports can get. If you are one of the few people yet to be captivated during a three week period that normally commences in the middle of March (hence the name) and concludes the first week of April, then let me explain how it works.
March Madness is an elimination basketball tournament that is played by sixty-eight (68) college teams from the USA. These 68 teams are comprised of the 32 automatic qualifiers who win their respective conference tournaments and 36 "at-large bids" selected by a committee. I will explain the difference below.
There are 32 Men's Division 1 college basketball conferences and each college basketball team belongs to a particular conference. These conferences can range from ten up to twenty teams. The college basketball regular season starts in early November and runs through to the respective Conference Tournaments which are typically held the week or two preceding March Madness. No matter the record of a team during the regular season, if they can win their conference final, they will gain automatic entry into the March Madness Tourney. So, the various conference tournaments provide 32 automatic entries.
A selection committee then decides the remaining 36 teams that comprise the 68-team field. The regular season is vital for teams to build their resumes via wins to be considered for an invite to the March Madness Tourney as if they do not win their end of season Conference Tournament that is their only way to get to be one of the 68 teams. Teams play predominantly within their conference but also play other teams from outside as well, generally at the beginning of the season, so the committee assesses every team's win/loss record at the end of the season and those deemed the best 36 that did not win their conference tournament are then invited to play March Madness.
So to summarize, teams can play in the March Madness Tourney by either qualifying directly (by winning their end of season Conference Final) or by being invited by a selection committee to an at-large team berth ( based on their regular season performances ) to be one of the 68 participants.
Once the 68 final teams are determined for March Madness, the selection committee then rank the teams from 1 to 68. They are then seeded into four quadrants where theoretically if the top four teams keep winning, they will end up in the Final Four and play two semifinals to determine who advances to the final. But this rarely happens, and there are many upsets during the tournament, and that is where the "Madness" arises.